Questions tagged [signature]
A digital signature proves that the owner of a private key produced or endorsed a given message. These are used in transactions to prove that an output can be spent in a transaction.
428
questions
1
vote
1
answer
43
views
Is the Z value generated before the (r, s) values?
I just want to confirm my understanding of signatures for P2PKH transactions.
The signature hash, z, is generated before generating the r and s values of a DER signature, correct?
- 85
1
vote
1
answer
41
views
Transaction keep beeing rejected "non-mandatory-script-verify-flag"
I'm developping Bitcoin integration for Microsoft Dynamics Business Central to offer enterprise capability to apply Bitcoin receivable and payable to accounting.
To send a transaction, I'm using ...
- 45
2
votes
1
answer
73
views
Why inputs' scriptSig are stripped before the whole transaction being signed?
In this video, the lecturer explains that before the whole transaction get signed, the scriptSig part of inputs are removed, and this causes the ability to perform transaction malleability attacks. My ...
- 1,123
2
votes
1
answer
85
views
Where are transaction signatures beside the scriptSig?
To spend a UTXO, we need to sign it (have the scriptSig). Then we can spend that UTXO to any address we want, which it wasn't included in the signature we produced for unlocking the UTXO. So we should ...
- 1,123
0
votes
0
answers
29
views
What does it mean when R, S values begin with zeroes?
I was hired to fix some typos in a WIF but I went into analyzing transactions instead then I found 3 R values that begin like this:
008505
008391
00a542
Then 2 S values begin like this:
S: 00db19
S: ...
-1
votes
1
answer
31
views
"Signature must be zero for failed CHECK(MULTI)SIG operation"
I want to broadcast signed transaction but I get this error how can I solve this I get this everytime.
"Signature must be zero for failed CHECK(MULTI)SIG operation"
RAW hex
...
1
vote
1
answer
233
views
python-bitcoin-utils - sendrawtransaction RPC error: {"code":-25,"message":"bad-txns-inputs-missingorspent"} when trying to broadcast my tx?
I am trying to create a bitcoin transaction to send all of the funds from tb1qj6zz96g8xgrwpgmdlvmkrjlwzz54sf47086yc9 to tb1qxgm8j0cq7tnftef3t563psl56gtmzxanm5c9uy. ...
- 243
1
vote
2
answers
142
views
Is there a set length that a signature can be?
I'm reading this page which describes the following method of creating a stack:
OP_0 <A sig> <B sig> OP_2 <A pubkey> <B pubkey> <C pubkey> OP_3
Sig Stack Pubkey ...
- 117
2
votes
1
answer
81
views
Validation of segwit v0-v1 tx automatically adds OP_CHECKSIG?
When I create a segwit transaction v0 (P2WPKH) or v1 (P2TR key-path spend) I do like that (let's spend a P2TR output):
Locking Script (of the P2TR output I'm spending): OP_1 PK_size PK
Witness: 1 (...
- 133
0
votes
1
answer
42
views
Continuation question about nonce randomness and verification of the randomness by signing parties
Original: Can a signer recover their own signature's nonce `k`?
Note that under normal circumstances it is infeasible to randomly generate the same nonce, so either a non-random nonce has to have ...
- 488
1
vote
1
answer
103
views
Can a signer recover their own signature's nonce `k`?
I am proofreading a blog post about nonce reuse. One point that comes up is whether someone could recover another person's private key if the other user reuses the same nonce. In that context, it was ...
- 69.8k
2
votes
1
answer
103
views
Error validating transaction: unexpected witness payload for non-witness script in a P2TR using script path
I am trying to create a raw transaction P2TR, spending a Taproot UTXO using the script path.
I did the following:
Create a random private key d and corresponding pubkey P (the internal pubkey)
...
- 133
4
votes
1
answer
271
views
non-mandatory-script-verify-flag (Invalid Schnorr signature) when I try to send a P2TR tx on testnet
I'm learning to create tx from scratch in order to understand better how bitcoin tx works and how they are structured. I learnt to create tx with legacy address, segwit v0 and I am now learning ...
- 133
5
votes
1
answer
311
views
Bitcoin Core file with the signing keys was removed from repo. How is the process supposed to be now?
Yesterday this PR was merged into the Bitcoin repository, and the process described at https://bitcoincore.org/download mentions that to validate the source code, you must download the txt file with ...
1
vote
0
answers
75
views
Is Curve25519 better option than Secp256k1?
Are signatures over Curve25519 better than over Secp256k1 or are there major drawbacks?
How do, for instance, EdDSA/Schnorr using Curve25519 compare with ECDSA/Schnorr for Secp256k1?
- 348
4
votes
2
answers
188
views
Signing taproot key-path transaction from rust-bitcoin
I'm trying to make a taproot HTLC using rust-bitcoin for an atomic swap protocol. My plan is that in the "happy case" of my protocol, the coins are spent with the key-path, and then there is ...
- 43
1
vote
0
answers
68
views
Anti-exfil protocol can't be verified on multiple hardware wallets
Regarding the nonce side channel attacks detailed in posts like this one by Blockstream. Which references this mailing list by Pieter Wuille. The idea is to add another layer of protection against a ...
- 11
1
vote
1
answer
24
views
LN-Channel: Do I have to use new private keys for each HTLCs out of security?
I have a question regarding the security of HTLCs in a LN-channel.
In a LN-transaction with multiple HTLCs (routings) to the destination one is using the signature of each node provider so that the ...
- 11
6
votes
1
answer
371
views
BLS signatures vs Schnorr
How do BLS signatures (or other pairing-based schemes) compare to Schnorr signatures in terms of cryptographic assumptions?
Is it faster to verify, say 100 (non-interactively) aggregated BLS ...
- 348
0
votes
1
answer
22
views
Getting a high s value rejection although s < N/2
Using the mempool app on my full node from mynode, when transmitting a raw tx with more than one output I get:
non-mandatory-script-verify-flag (Non-canonical signature: S value is unnecessarily high)....
1
vote
2
answers
86
views
How many digital signatures appear in a block?
I am wondering how many times ECDSA digital signature are used across transactions in one block.
Let's take for example Block #735,273. It contains 405 transactions. My understanding is that each ...
- 13
-1
votes
1
answer
65
views
Question regarding the Z value of bitcoin Transaction
Is there such a value as a negative Z or inverse Z related to the original Z value, which is the double SHA256 of the unsigned tx+01000000. I know there is a negative S value, is there a negative Z as ...
- 1
2
votes
1
answer
179
views
Were uncompressed public keys always supported by Bitcoin?
I was wondering when compressed public keys were introduced to bitcoin, then I saw this quote from this answer:
The original Bitcoin software didn't use compressed keys only because their use was ...
- 779
-1
votes
1
answer
76
views
What are Known Bits in a bitcoin Transaction?
How do I know if my signatures has leak/weak signatures?
Is there a website or script where I can input my signatures to check for weak/leak Nonce part?
0
votes
1
answer
47
views
Exploiting the use of signature?
I've just learned signatures and why they're used in blockchain.
As I understand there is a key pair that consist of one public key and one private key:
Private keys are used to sign a message(...
- 21
1
vote
2
answers
127
views
Can someone calculate my private key if I send the same amount to one address?
If I send the exact same amount to the same address in two separate transactions, can someone calculate my private key from the scriptSig? Will the signature (S) and the message (Z) be same?
13
votes
1
answer
2k
views
Is any 256-bit combination a Bitcoin private key?
I've recently been implementing a simple Bitcoin wallet and some libraries seem to disagree with address derivation from the same WIF private key, and thus wouldn't sign transactions. After that, I ...
- 255
0
votes
0
answers
124
views
Is there software that can scan for reused R-values?
Is there any up-to-date program that can check for reused R-value for a specific Bitcoin address? (I don't want to scan the whole blockchain, just for a particular address.)
1
vote
1
answer
46
views
Why we need to repalce the ScriptSig with the previous ScriptPubKey when calculate the per input signature hash?
I'm reading Programming Bitcoin. And in Chapter7, the author talked about the way how signature hash is calculated by replacing the transaction's ScriptSig with the corresponding previous ScriptPubKey....
- 27
2
votes
1
answer
140
views
How and when were high-s signatures made non-standard?
I was just trying to pin-point which BIP made high-s signatures non-standard. BIP62 proposed it as a new consensus rule, but was withdrawn. I couldn't find it in another BIP.
- 69.8k
0
votes
1
answer
76
views
btc transaction by Digital signature
I have old btc wallet and I have Digital signature but i don't have Private key , Is there any way for withdraw btc from wallet just by Digital signature ?
- 1
1
vote
1
answer
113
views
Can The Redeem Script Consist Of Only 1 Public Key In P2SH Transactions:
I have a few questions relating to Bitcoin Signatures And P2SH:
Why is P2SH used as opposed to other forms? Is it still prevalent today - has SegWit made it redundant or less useful, if not, what is ...
- 157
0
votes
1
answer
57
views
Where Is Signature Data Stored In Post-SegWit Transactions?
If i'm correct, i am pretty sure that signature data such as the scriptsigsize
and scriptsig is stored outside the Tx_Data of a Bitcoin transaction. But then where is it stored? Is it in the block or ...
- 157
1
vote
1
answer
87
views
How is a Bitcoin transaction signed using ECDSA?
I am quite familiar with the way secp256k1 ECDSA works as well as the equations that are utilised. However, I have no idea how this ECDSA applies to signing Bitcoin (SegWit Format) and transferring it ...
- 157
2
votes
1
answer
179
views
SegWit signing algorithm and its improvement
I was reading about Segregated Witness upgrade from the book Mastering Bitcoin by Andreas and there were some questions I have not figured out. I am appreciated to get some of your help!
A) There was ...
- 57
2
votes
1
answer
337
views
Can the difference be determined between two nonces k1, k2, having a linear relationship if the nonce and private key are unknown, i.e., k2 - k1 = n?
My question is related to weak signature vulnerability testing where a hypothetical attacker does not know the values of the nonce or private key itself, but can determine that the nonce 'k1' is ...
2
votes
1
answer
251
views
Segwit includes the input amount in the SignatureHash. What possible attack can this prevent?
Legacy transactions only include transaction components in the SignatureHash, but segwit transactions also add the amounts of inputs in the SignatureHash.
Quoting from the Mastering Bitcoin Book:
...
1
vote
1
answer
33
views
What is maxsigcachesize?
-maxsigcachesize= Limit sum of signature cache and script execution cache sizes to
What is this?
What is a sigcache?
What happens if it is set low and Can it have a bad effect?
- 466
2
votes
1
answer
171
views
How to calculate the public key, compute point P and create signature using ECDSA?
I'm quite new to the intricacies of bitcoin cryptography and ECDSA and elliptic curve cryptography has me quite stymied. I am faced with a curve with the equation: y^2 = x^3 + 7 of order N=39 with ...
- 21
1
vote
1
answer
94
views
Cryptographic digital signatures
I have a doubt since the public keys are known to everyone, so someone could falsify a transaction by writing down a deposit from a public address to another public address in a new block and solving ...
- 11
1
vote
1
answer
85
views
Order of Signatures in Multisig-Scheme
3 Entities (A/B/C) create a collaborative Multisig Wallet (e.g. 2-of-3).
A creates an unsigned TX and shares it with B/C. They (B/C) sign and broadcast.
Looking at the TX on the network, can A make ...
- 11
1
vote
1
answer
101
views
Standard library for schnorr signature algorithm
I am trying to create a blockchain demonstration to get used to the technology. The thing is: I want to use Schnorr signatures, but I can't seem to find a library for that, and I want to make sure ...
- 11
1
vote
1
answer
33
views
Does signing a message as specified in AOPP incur a fee?
Does signing a message as specified in Address Ownership Proof Protocol (AOPP) incur a fee? I think not - there is nothing written in the specification about broadcasting
anything to the Bitcoin ...
- 530
0
votes
1
answer
35
views
Is it Possible to Create Signature Chains for Private Keys to Sign Transactions with? Similar to how Certificate Authorities Use Intermediate Certs?
I am wondering if it is possible to implement this flow with bitcoin private keys, similar to how certificate authorities have a root cert and an intermediate cert used to sign csr's. It would be ...
- 13
2
votes
1
answer
61
views
Bitcoin transaction inquiry
if suppose a someone offers a prize for anyone that can solve a specific challenge, how will the solver make sure that he/she collects the reward? Does the solver need to send the solution directly to ...
3
votes
1
answer
289
views
What is the probability of an ECDSA signature being less than 71 bytes
Since DER requires R and s values being minimally encoded signed integers, they could be less than the expected 32 bytes. What is the probability that one or both of R and s are less than 32 bytes for ...
- 66.4k
1
vote
3
answers
67
views
Why can't I modify someone else's transactions, if I have their signature data?
As I know, signature system is adding signature to end of transaction. And doesn’t hash transaction, so others can know my signature.
If I can send a message directly to the node, can I use other’s ...
- 11
2
votes
2
answers
118
views
What is the relationship between r in signature and the public key
I've been reading about ECDSA in here.
Step 11 says that
you only need the ‘x‘ value (20 bytes) for the signature, and that value will be called ‘R‘
Does that say that R is the x-coordinate of the ...
1
vote
1
answer
124
views
How long is SIGHASH?
I am reading these two posts 1 2, and following step by step.
I almost understand, but I still have some questions.
Before signing, input script should be removed and replaced by pre locking script. ...
1
vote
1
answer
94
views
How many times and where exactly is ECDSA used in Bitcoin?
I'm currently a little confused about where exactly ECDSA is used in the transaction process... some resources seem to say it's used once, whereas others seem to say it's used three times.
Which is ...
- 13